Heat Health Plans Guidelines - Released 2018 health.govt.nz - Ministry of Health

Heat Health

Released 2018   health.govt.nz
Citation: Ministry of Health. 2018. Heat Health Plans: Guidelines.
Wellington: Ministry of Health.

Published in December 2018 by the Ministry of Health
PO Box 5013, Wellington 6140, New Zealand

ISBN 978-1-98-856834-8 (online)
HP 7003

This document is available at health.govt.nz

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Heat Health Plan: Guidelines                                   1

  Introduction                                                 1
     Guideline format                                          1
     Acknowledgements                                          2

  Objectives and scope                                         2
     Objectives                                                2
     Statutory framework                                       2

  Heatwave hazard                                              3
     Defining extreme heat and heatwaves                       3
     Early warning signs                                       4
     Other risks factors and impacts                           5
     Climate                                                   5

  Health effects of heatwaves                                  6
     Effects of heat on health                                 6
     Vulnerable populations                                    8
     Equity                                                    9
     Rural communities                                         9
     Urban heat islands                                        9

  Heat health actions                                        10
     Preparing a Heat Health Plan                            10
     Communication strategy                                  11
     Taking action                                           12

  Further information                                        14

  References                                                 15

                                           HEAT HEALTH PLANS: GUIDELINES   iii
Heat Health Plan:
Strong evidence shows that extreme heat and heatwaves have negative impacts on
health (Hajat et al 2010; Kravchenko et al 2013; Luber and McGeehin 2008). Extreme
heat can cause illness and death, but effective planning and actions can reduce its
effects on health. Because effects of heat are associated with relative rather than
absolute temperatures, even in New Zealand’s temperate climate people can
experience negative health effects with modest increases in seasonal temperature.

There is no formal definition for heatwaves in New Zealand. However, climate change is
predicted to cause both average and maximum temperatures to rise, and the number
of hot days experienced in New Zealand is expected to increase (Ministry for the
Environment 2016).

Many countries around the world already have Heat Health Plans in place (Public
Health England 2015a; Victoria State Government Health and Human Services 2015).
Some are countries already considered hot, such as Australia, but others have
temperature climates similar to New Zealand’s, like England. Heat Health Plans set out
the actions needed to prepare for periods of high temperatures, as well as important
actions during and after those periods. These actions apply to individuals,
organisations and national, local and regional government.

Everyone is vulnerable to extreme heat. However, babies and infants, older people,
those with pre-existing medical conditions or on certain medications, and people living
alone are more at risk.

These Heat Health Plan Guidelines are aimed at health and community service
providers, district health boards, public health units, local government and other
community organisations to help them prepare their own heat health response plans.

Guideline format
The main sections of these guidelines are:
•   objectives and scope – objectives and scope for these guidelines and how they fit
    into existing statutory frameworks
•   heatwave hazard – the potential of heatwaves as a health hazard and the relevance
    of heatwave health planning in New Zealand
•   health effects of heatwaves – heatwave-related health effects and vulnerable populations
•   heat health actions – risk management actions.

                                                                 HEAT HEALTH PLANS: GUIDELINES   1
    These guidelines have been adapted for use in New Zealand from the Victoria
    Department of Health and Human Services’ Heat Health Plan for Victoria (Victoria State
    Government Health and Human Services 2015) and Heatwave Planning Guide (Victoria
    State Government Health and Human Services 2009), and also Public Health England’s
    Heatwave Plan for England (Public Health England 2015a).

    Objectives and scope
    This section sets out the aims of these guidelines, defines their scope and describes
    their statutory framework.

    The aims of these Heat Health Plan Guidelines are to:
    •   raise awareness of the negative health effects of high temperatures
    •   encourage and guide organisations to prepare Heat Health Plans
    •   highlight which sectors of the population are most vulnerable to high heat, and why
    •   outline the actions that can reduce the effects of high temperatures
    •   develop consistent messaging about the health impacts of extreme heat
    •   outline the potential impacts of extreme heat events on health services.

    Studies have shown that many of the hospitalisations that occur during heatwaves are
    for preventable conditions that could have been avoided with better planning and
    communication of heat health messages (Hopp et al 2018). It is recommended that
    health and community service providers, district health boards, public health units and
    local government prepare their own Heat Health Plans as part of their emergency
    planning. Including heat health planning as part of emergency planning is also
    encouraged for individuals and families, schools, businesses and community groups.
    This will lead to better health outcomes for all and improve community resilience to
    periods of extreme heat.

    Statutory framework
    These Heat Health Plan Guidelines support the National Health Emergency Plan (NHEP)
    (Ministry of Health 2015a).These guidelines should be read in conjunction with the
    National Civil Defence Emergency Management (CDEM) Plan and guide (Ministry of
    Civil Defence & Emergency Management 2015), in particular the hazard-specific
    information on heat (Ministry of Civil Defence & Emergency Management 2010).

The Civil Defence Emergency Management Act 2002 (and amendments) and Ministry
of Civil Defence & Emergency Management’s National CDEM Plan outline the roles and
responsibilities of key government agencies in an emergency.

The Ministry of Health’s NHEP specifies how the health and disability sector fits in the
context of New Zealand emergency management and provides the overall strategic
framework for response. A number of specific subplans, including these Heat Health
Plan Guidelines, underpin the NHEP.

Heatwaves are not identified as a potential hazard of national significance in the
National CDEM Plan, but the NHEP identifies extreme weather incidents (hot or cold) as
a hazard at local to regional scales. Locally and regionally, local governments and
district health boards are responsible for preparing their own emergency response and
health emergency plans. It is envisaged that local governments and district health
boards will prepare specific Heat Health Plans that integrate with existing emergency
management documents. The Ministry of Civil Defence & Emergency Management’s
(2010) hazard-specific information on heat offers guidance for individuals on how to
cope with a heatwave.

District health boards should be considering the development of Heat Health Plans for
their regions, and leading their development across provider arms and public health

Heatwave hazard
Even moderate increases in temperature beyond seasonal norms are associated with
an increase in ill health and death. With the prospect of increasing temperatures and
more hot days in the future due to climate change, it is important that the country is
prepared for extreme heat events. This section discusses definitions and early warning
signs for detecting heatwaves, risk factors that exacerbate the effects of heatwaves,
and the potential effects of climate change on temperatures in New Zealand.

Defining extreme heat and heatwaves
There is no worldwide consensus on a definition of extreme heat or heatwave events.
Different countries have different conditions for extreme heat events based on their local
climate, which may include factors related to heatwave formation such as maximum daily
temperature, average daily temperature, daily minimum (night-time) temperature,
duration and humidity (Nairn and Fawcett 2013). It is the increase above average
temperatures, rather than an absolute temperature, that causes adverse impacts on
health. Evidence indicates that the effects of heatwaves on health are greater in
temperate areas, as extreme heat occurs infrequently so residents in these areas are not
used to it (Chestnut et al 1998; Keatinge et al 2000; McMichael et al 2008).

While New Zealand does not yet have a formal definition, the World Meteorological
Organization (2015) defines a heatwave as:

                                                                HEAT HEALTH PLANS: GUIDELINES   3
a marked unusual hot weather (max, min and daily average) over a region
        persisting at least two consecutive days during the hot period of the year based
        on local climatological conditions, with thermal conditions recorded above given

    If we apply this definition to New Zealand, it is necessary to determine the appropriate
    thresholds for different regions based on demonstrated risks to human health (which
    will be related to the local climatological conditions). Some regions of New Zealand are
    at higher risk of experiencing heatwaves, and this risk will change as the effects of
    climate change are realised.

    Some countries such as Australia and England issue heatwave warnings through their
    national weather bureaus. The warnings are issued when the ‘trigger’ conditions are
    met for a particular location. They are a signal to organisations and communities that
    they need to take extra health precautions.

    No weather warnings about extremes in temperature are currently issued in New
    Zealand, although a system may be developed in the future. However, by recognising
    the early warning signs of heatwaves, and their own individual risk factors,
    organisations can prepare for such events and in this way reduce the risks to human

    Early warning signs
    With or without a national heatwave alert system, it is important to understand the
    early warning signs of heatwaves so that organisations can put their Heat Health Plans
    into effect and make appropriate preparations. Some factors contributing to the
    development of heatwaves are (Kravchenko et al 2013; Nairn and Fawcett 2013):
    •   day-time temperatures – average summer temperatures in New Zealand range
        from around 18 degrees in cooler areas such as Dunedin, Invercargill and the
        Chatham Islands to around 25 degrees in warmer areas such as Central Otago,
        Marlborough, Hawke’s Bay, Gisborne, Tauranga and Whangarei (NIWA 2013). Daily
        maximum and average temperatures that exceed these averages may indicate an
        imminent heatwave
    •   night-time temperatures – cooler temperatures at night-time provide respite from
        heat during the day. Elevated night-time temperatures, which may be exacerbated
        by the urban heat island effect (see the following section on the health effects of
        heatwaves), can be another risk factor for heatwave conditions
    •   humidity – high levels of humidity can make it feel hotter (perceived heat) and
        negatively affect the body’s cooling mechanisms
    •   duration – extended periods of hot and/or humid weather increase the risk to and
        impact on health.

Other risks factors and impacts
Other risk factors and impacts may exacerbate the effects of a heatwave and cause
more widespread disruption during a period of extended heat. Examples include
(Public Health England 2015a):
•   disruption to transport networks when road surfaces deteriorate due to the heat
•   traffic congestion, which keeps people in cars for long periods
•   interruption to power supplies, particularly during times of drought or due to
    increased electricity use to run air conditioning units
•   limited availability of and access to air conditioning
•   reduced air quality with no wind
•   reduced water quality due to algal blooms
•   odour, dust and vermin infestations
•   fires
•   impacts on animal welfare
•   water shortages
•   increased risk of climate-sensitive illnesses, including food-borne illness outbreaks.

These factors may make it more difficult for service providers to operate at the
required capacity. For example, they may lead to increased workloads for staff, staff
absenteeism and/or disruptions to supply chains.

In preparing their own Heat Health Plans, it is important that individual organisations
consider all of the risk factors and impacts, in addition to the examples listed above,
that may be relevant to them during a heatwave.

Variations and trends in New Zealand’s climate can increase or reduce the likelihood of
heatwaves. It is important for organisations to be aware of these variations and trends
when preparing their own Heat Health Plans.

Climate cycles
Climate in New Zealand is affected by the El Niño Southern Oscillation (ENSO). ENSO is
an irregular climate cycle that disrupts normal patterns of wind and rainfall. The two
extremes of the cycle are known as El Niño and La Niña. In El Niño years, there is
typically an elevated risk of drought in the east coast of New Zealand and more rain in
the west. During La Niña years, warmer temperatures typically occur over much of the
country, and more rain is experienced in the north-east of the North Island and less
rain in the south of the South Island. The effects of ENSO are sufficiently significant to
warrant planning and management action when an El Niño or La Niña event is
expected or in progress (NIWA 2018).

                                                                 HEAT HEALTH PLANS: GUIDELINES   5
Climate change
    Average temperatures are projected to continue rising, and extreme weather events –
    including extremely high temperatures and heatwaves – are also expected to become
    more likely (Ministry for the Environment 2016; Royal Society of New Zealand 2016).
    The number of days when temperature exceeds 25 degrees Celsius is expected to
    increase between 40 and 100 percent by 2040 and between 40 and 300 percent by
    2090 (Ministry for the Environment 2016).

    Health effects of heatwaves
    Heatwaves can be serious events that cause death and illness. In Australia, heatwaves
    are responsible for more deaths than any other natural hazard (Nairn and Fawcett
    2013). A heatwave in Europe in 2003 caused an estimated 35,000 deaths across the
    continent (Ministry of Civil Defence & Emergency Management 2010). In New Zealand,
    heatwaves of this magnitude are rarely experienced, but even so in Auckland and
    Christchurch an average of 14 high-heat-related deaths occur per year in people aged
    over 65 years (McMichael et al 2003). This number is likely to increase as climate
    change causes temperature levels in New Zealand to rise (McMichael et al 2003; Royal
    Society of New Zealand 2017).

    This section describes the health impacts of heatwaves and which sectors of the
    population are most vulnerable.

    Effects of heat on health
    Many of the adverse health effects from excessive heat are preventable. Under normal
    warm conditions, the body regulates temperature by producing sweat that evaporates
    and cools the body. However, when a combination of high heat and high humidity
    occurs, the evaporation slows and the body must work harder to maintain a normal
    temperature. This extra work stresses the body and can lead to illness and death (Hajat
    et al 2010; Kjellstrom et al 2016; Kravchenko et al 2013; Public Health England 2015b).

    The main causes of illness and death during a heatwave are related to cardiac
    conditions and to asthma and respiratory illness. Specifically, the cardiovascular system
    can experience stress from increased pumping of blood to the skin to cool the body,
    while higher levels of air pollution exacerbate respiratory symptoms. Kidney disease,
    diabetes, nervous system disease and cancer have also been identified as factors
    contributing to death during extreme heat events (Bunker et al 2015; Hajat et al 2010;
    Public Health England 2015b).

    Table 1 describes other effects of high heat on health and how to treat them. General
    actions that can prevent or mitigate these health effects include staying cool and out
    of the heat, limiting physical activity and keeping hydrated (Public Health England

Table 1: Heat-related conditions

 Condition       Symptoms                                 Cause                                     Treatment

 Heat rash       Small, red, itchy bumps                  Excessive sweating                        Move to a cooler, less humid environment. Keep the affected area dry. Dusting
                                                                                                    powder may be used to increase comfort but avoid ointments or creams

 Heat cramps     Muscular pains and spasms, usually       Low salt level in the muscles due to      Those with heart conditions or on a low-sodium diet need medical
                 in the abdomen, arms or legs             dehydration and electrolyte               attention. Otherwise:
                                                          imbalance causes painful cramps.          •   replenish fluids (drink water or electrolyte replacement solutions)
                                                          Heat cramps may be the first sign of
                                                                                                    •   rest in a cool environment
                                                          heat exhaustion and are often the
                                                          first sign the body is having trouble     •   do not return to strenuous activity for a few hours after the cramps subside
                                                          with the heat                             •   seek medical attention if cramps do not subside within one hour

 Sunburn         Red painful skin that is warm to the     Overexposure to UV radiation              Sunburn leads to an increased risk of skin cancer. Severe sunburn may require
                 touch. Severe sunburn may result in                                                medical attention. Otherwise:
                 fever, blistering and severe pain                                                  •   avoid repeated sun exposure
                                                                                                    •   apply cold compresses or moisturising lotion (not salve, butter or
                                                                                                        ointment) to affected area
                                                                                                    •   do not break blisters

 Heat            Heavy sweating, paleness, muscle         Dehydration. Blood flow to the skin       Medical attention is required if symptoms are severe or for those with
 exhaustion      cramps, tiredness, weakness,             increases while blood flow to vital       heart problems or high blood pressure. Otherwise:
                 dizziness, vomiting, headache, fast      organs decreases, resulting in a mild     •   replenish fluids
                 and weak pulse, fast and shallow         form of shock. If left untreated, may
                                                                                                    •   rest in a cool environment
                 breathing                                evolve into heatstroke
                                                                                                    •   cool down by taking a cool shower or bath
                                                                                                    •   seek medical attention if symptoms worsen or last longer than one hour

 Heatstroke/     High body temperature (above             Failure of body’s thermoregulation        Immediate medical attention required.
 sunstroke       39.4 degrees Celsius), confusion,        mechanism. Can result in cell death,      •   Call for medical assistance.
                 disorientation, unconsciousness, red     organ failure, brain damage or death
                                                                                                    •   Cool down in whatever way possible.
                 hot dry skin (no sweating), throbbing
                 headache, nausea, rapid strong pulse                                               •   Monitor body temperature and continue cooling efforts until body
                                                                                                        temperature drops below 38.5 degrees Celsius.

Source: Adapted from Victoria State Government Health and Human Services (2009), Ministry of Civil Defence & Emergency Management (2010) and Public Health England (2015b)

                                                                                                                                              HEAT HEALTH PLANS: GUIDELINES       7
Vulnerable populations
    Some people’s ability to regulate body temperature is compromised, which makes the
    body more vulnerable to overheating. This could be due to age, the effects of some
    medications or chronic illness. Risk factors for heat-related illness include (Kravchenko
    et al 2013; Public Health England 2015b; Victoria State Government Health and Human
    Services 2015):
    •   older age – especially those over 65 years of age, or living on their own and socially
    •   chronic, acute and severe illness – including heart conditions, diabetes, respiratory
        or renal insufficiency, Parkinson’s disease and severe mental illness. Medicines that
        potentially affect renal function, the body’s ability to sweat, thermoregulation or
        electrolyte imbalance can make people in this group more vulnerable to the effects
        of heat
    •   pregnant women – who are more susceptible to heat exhaustion and heatstroke,
        which may in turn lead to birth defects and other reproductive problems (National
        Institute for Occupational Safety and Health 2018)
    •   young age – with infants vulnerable due to their immature thermoregulation and
        high level of dependency
    •   homelessness – due to higher rates of chronic disease, smoking, respiratory
        conditions, substance dependencies and mental illness among this group, as well as
        social isolation, lack of shelter and vulnerability to the effects of urban heat islands
    •   alcohol and/or drug dependence – which is associated with poorer overall health
        and social isolation
    •   inability to adapt behaviour to keep cool – which may include, for example, those
        with Alzheimer’s disease, a disability or mental illness or who are bed bound
    •   environmental factors and overexposure – for example, living in urban areas,
        undertaking outdoor activities or jobs 1 that involve a high level of physical exertion,
        and attending outdoor public events
    •   language barriers – difficulty in understanding heat health messages and warnings.

    Inadequately ventilated housing and lack of access to mechanical cooling systems can
    be other exacerbating factors (Hajat et al 2010), which may disproportionately affect
    those of lower socioeconomic status. In a moderate heatwave, it is generally vulnerable
    people that are affected; in a severe heatwave, however, fit and healthy people can also
    be affected (Public Health England 2015b).

        For WorkSafe New Zealand guidance on temperatures in the workplace and employers’ obligations, go
        to: https://worksafe.govt.nz/topic-and-industry/temperature-at-work/

The effects of heatwaves will not be evenly distributed in New Zealand. Some regions
are expected to see a greater increase in the number of hot days than others. For
example, the top half of the North Island, Gisborne and Hawke’s Bay are projected to
have the greatest number of hot days in the future. These regions have large
populations of Māori and Pacific peoples, as well as higher proportions of people living
in areas of socioeconomic deprivation. Heatwaves could potentially increase the levels
of inequity in these areas.

Rural communities
Heatwaves also disproportionately affect primary industries such as farming. Rural
communities are more vulnerable during periods of hot weather than those living in
urban and suburban centres, particularly in terms of water and food security and access
to health services. Because drought also disproportionately affects them, heatwave
planning and drought planning in rural communities should inform each other.

Urban heat islands
The effects of heatwaves are more keenly felt in urban areas due to the larger area of
heat-absorbing materials such as pavement, reduced evaporation and shading from a
lack of plants and trees, greater inputs of heat from buildings and transport, and higher
levels of air pollution (Public Health England 2015b). With the ‘urban heat island’ effect
these conditions create, temperatures in cities can be as much as 10 degrees Celsius
higher than in surrounding areas (Kravchenko et al 2013). The heat that buildings and
pavements absorb during the day is released during the night, locally elevating night-
time temperatures (Luber and McGeehin 2008; Public Health England 2015b) and
further contributing to heatwave conditions.

The form and intensity of the urban heat island effect depend on the local
meteorological conditions, geography and urban development of an area. Long-term
planning that considers building materials and green spaces can help to reduce its
effects. For example, trees provide shade and allow cooler air to accumulate and
circulate at ground level. Planting trees and other vegetation also alleviates the effects
of extreme heat by providing shade and through the cooling effect of evaporation.
Water features such as lakes, ponds and fountains are other ways of helping to cool
the environment (Public Health England 2015b).

                                                                 HEAT HEALTH PLANS: GUIDELINES   9
Heat health actions
     Numerous organisations are involved in protecting, managing and servicing the health
     needs of the New Zealand population. This section outlines the actions these
     organisations can take throughout the year to prepare for heatwaves.

     Preparing a Heat Health Plan
     Heat Health Plans should outline the actions and systems in place to support those
     most at risk during periods of extreme heat. They should be integrated with existing
     emergency response plans and include the four Rs of emergency management:
     reduction, readiness, response and recovery. The National Health Emergency Plan
     contains guidance on the four Rs of emergency management and how to prepare a
     health emergency plan, which is relevant to preparing a Heat Health Plan.

     The Victoria State Government has prepared guidance for developing heatwave plans
     that may be useful in developing Heat Health Plans in New Zealand as well. To access
     the Victorian guides, go to:

     Heat Health Plans need to consider both acute effects of heatwaves (that is,
     responding to incidences of heat-related illness) and support functions through
     engagement with other agencies (for example, the Ministry for Primary Industries
     during a drought).

     Items that might be considered as part of a Heat Health Plan include (Victoria State
     Government Health and Human Services 2009):
     •   identifying appropriate stakeholders (representatives from affected groups and
         other organisations that will be involved in responding)
     •   setting appropriate staffing levels that take account of staff and client safety in hot
     •   considering staff wellbeing (as well as clients) during an extreme heat event and
         providing training to staff on explaining risks of high heat to clients
     •   considering appropriate actions to minimise effects of extreme heat and responses
     •   incorporating heat events into communication strategies and business continuity
         service plans
     •   maintaining continuity of care during an extreme heat event
     •   keeping buildings cool and shaded
     •   having loose, cool clothing available
     •   having water available
     •   monitoring indoor temperatures

•   storing medicines appropriately
•   taking long-term actions to reduce heat impacts such as urban planning,
    developing green spaces and reducing carbon emissions.

Communication strategy
As part of the heat health planning process, organisations should develop a
communication strategy. This strategy should target specific groups for information,
establish clear and consistent messages and set out timeframes and methods of

Internal communication
An internal communication strategy should include the ability to:
•   advise staff about actions, protocols and communication related to the Heat Health
•   alert staff if a period of extreme heat is forecast
•   advise staff when an extreme heat event is finished.

Stakeholder communication
The Heat Health Plan should set out how and when stakeholders will be engaged.

Communication messages
Consistent messages about the risks of extreme heat are needed to increase the
likelihood of behaviour change and reduce health impacts (Luber and McGeehin 2008).
Messages during an extreme heat event need to provide timely and accurate
information. Key information includes:
•   which people are most at risk from the impacts of high heat, including babies and
    infants, the elderly and those with underlying medical conditions
•   actions to prevent the impacts of high heat, including staying out of the sun,
    avoiding extreme physical exertion and drinking lots of water. Messages should also
    advise people to be SunSmart (see www.sunsmart.org.nz); to keep their houses
    cool by opening windows to catch the breeze and keeping curtains or blinds closed
    to keep the sun out; and not to leave children, the elderly or pets alone in parked
    cars. Civil Defence has also prepared advice for individuals and families, including
    advice for looking after pets and livestock, during heatwaves (Ministry of Civil
    Defence & Emergency Management 2010)
•   what to do if feeling unwell – seek medical help if feeling weak or dizzy or if having
    intense thirst or a headache.

                                                                 HEAT HEALTH PLANS: GUIDELINES   11
Taking action
     When preparing a Heat Health Plan, it is important that each organisation considers its
     own needs in periods of hot weather and determines levels of action that are
     appropriate for its specific requirements. Actions at national, regional and local levels
     are needed to protect health, and the most effective responses will be coordinated
     between organisations at these different levels. Planning also needs to consider that
     heatwave effects can be localised or experienced more widely.

     Figure 1 provides overall guidance for heat health planning actions at national,
     regional and local levels, and also suggests some trigger levels for escalating the
     response. Ideally the trigger levels would correspond to a change in risk to health.
     Note that because New Zealand has no formal heat-related notification system,
     individual organisations will need to consider setting trigger levels, monitoring weather
     conditions and implementing Heat Health Plans as appropriate.

Figure 1: Guidance on heat action escalation levels

                                    Planning and preparation
                                       Before summer / year round

  All organisations:
  •   promote preparation of Heat Health Plans
  •   engage with key stakeholders to raise awareness of risks of extreme heat
  •   prepare or update Heat Health Plans in coordination with other organisations
  •   identify groups of vulnerable people
  •   consider long-term planning opportunities to reduce impacts of extreme heat
  •   provide information and training to staff
  •   prepare heat health communications and advice.

                                        Heatwave monitoring
                                       Normal summer temperatures

  All organisations:
  •   monitor weather conditions
  •   carry out preparation actions.

                                             Heat forecast
                        Period of hot (above average) temperatures forecast

  All organisations:
  •   take preparation steps in line with Heat Health Plans
  •   monitor weather conditions.

                                         Heatwave response
                           When predetermined trigger levels are reached

  •   All organisations respond in line with Heat Health Plans.
  •   Regional organisations (ie, district health boards and local CDEM groups) take a lead role in
      response, including by coordinating resources and issuing communications.
  •   National organisations monitor and support as required.

                               Return to normal summer temperatures

  All organisations:
  •   provide recovery and support in line with Heat Health Plans
  •   carry out evaluations and lessons learnt
  •   distribute lessons learnt to other organisations.

                                                                         HEAT HEALTH PLANS: GUIDELINES   13
Setting trigger levels
     Trigger levels need to be set to suit local conditions. Currently only limited information
     about the effects of heat on health is available that is specific to New Zealand. In time,
     this body of knowledge will grow, allowing organisations to make evidence-based
     decisions about trigger levels for their area. In the meantime, the following resources
     are available to help with setting trigger levels.
     •   Overseas heat health planning and guidance can provide some ideas on the types
         of trigger levels that could be set. Public Health England (2015a, 2015b) and Victoria
         State Government Health and Human Services (2009, 2015) have both developed
         extensive resources on heat health planning.
     •   The National Institute of Water and Atmospheric Research (NIWA) monitors
         drought conditions using the New Zealand Drought Index. Although the index
         primarily relates to low levels of rainfall, it includes measures of temperature and
         could be used as an informative indicator.
     •   Previous climate range reports have used a temperature of 25 degrees Celsius to
         designate ‘hot days’
     •   Local CDEM offices can help organisations understand their local and regional

     Further information
     The following guidance is available from the Ministry of Health’s website
     •   Protecting Your Health in an Emergency (Ministry of Health 2015b), a booklet that
         provides advice for individuals and families on keeping themselves healthy during a
         wide range of emergencies
     •   The National Health Emergency Plan (Ministry of Health 2015a).

     The following guidance is available from the Ministry of Civil Defence & Emergency
     Management’s website (www.civildefence.govt.nz):
     •   Working from the Same Page: Consistent Messages for CDEM. Part B: Hazard-specific
         information – Heat (Ministry of Civil Defence & Emergency Management 2010),
         which provides advice for individuals and families, including advice for looking after
         pets and livestock
     •   The Civil Defence Emergency Plan (Ministry of Civil Defence & Emergency
         Management 2015).

     The SunSmart website (www.sunsmart.org.nz) provides information about protecting
     yourself and others from UV radiation from sunlight.

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Keatinge WR, Donaldson GC, Cordioli E, et al. 2000. Heat related mortality in warm and
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